The invention discloses an
algorithm for positioning the accurate mountain fire and calculating a
vertical distance between a mountain fire edge and an overhead
transmission line. After the mountain fire is discovered through a camera, a planar two-dimensional coordinate
system o-xy, an image space rectangular coordinate
system S-xyz, a ground photography coordinate
system O-XYZ and an image spaceauxiliary coordinate system S-XYZ are constructed based on the
photogrammetry principle, p is an image point, P is a
fire point, S is the origin of the camera photographic center, and o is the originof the image center; three-dimensional attitude angles during image shooting are measured through utilizing a three-dimensional electronic
compass fixedly mounted on the camera in real time, including the
azimuth angle (phi), tehe inclination angle (
omega) and the roll angle (kappa); through image point space coordinate transformation, a collinear
conditional equation satisfying the image point p, the
fire point P and the origin S of the camera photographic center is constructed, and the equal-division search method is utilized to acquire the three-dimensional coordinate of the
fire point.